Detecting and identifying misplaced items using a sensor array

Abstract

An object tracking system that includes a sensor and a tracking system. The sensor is configured to capture a frame of at least a portion of a rack within a global plane for a space. The tracking system is further configured to receive the frame, to determine a pixel location for the first person, and to determine a person is within the predefined zone associated with the rack. The tracking system is further configured to identify the plurality of items in a digital cart associated with the person, to identify an item from the digital cart associated with the first person, and to remove the identified item from the digital cart associated with the person.

The invention claimed is: 
     
       1. An object tracking system, comprising:
 a sensor configured to capture a frame of at least a portion of a rack within a global plane for a space, wherein:
 the global plane represents (x,y) coordinates for the space; 
 the frame comprises a plurality of pixels; 
 each pixel from the plurality of pixels is associated with a pixel location comprising a pixel row and a pixel column; and 
 the frame comprises a predefined zone associated with the rack, wherein the predefined zone is proximate to a front of the rack; 
 
 and 
 a tracking system operably coupled to the sensor, comprising:
 one or more memories operable to store a first digital cart associated with a first person, wherein the first digital cart identifies a first plurality of items, and store a second digital cart associated with a second person, wherein the second digital cart identifies a second plurality of items; and 
 one or more processors operably coupled to the one or more memories, configured to:
 receive the frame; 
 determine a pixel location for the first person, wherein the pixel location for the first person comprises a first pixel row and a first pixel column of the frame; 
 determine a pixel location for the second person, wherein the pixel location for the second person comprises a second pixel row and a second pixel column of the frame; 
 determine the first person is within the predefined zone associated with the rack in the frame based on the pixel location for the person; 
 determine the second person is not within the predefined zone associated with the rack in the frame based on the pixel location for the second person; 
 leave unmodified the second digital cart of the second person; 
 identify the first plurality of items in the first digital cart associated with the first person; 
 identify a first item from the first plurality of items associated with the first person; and 
 remove the first identified item from the first digital cart associated with the first person. 
 
 
 
     
     
       2. The system of  claim 1 , wherein:
 the predefined zone associated with the rack is associated with a range of pixel columns in the frame and a range of pixel rows in the frame; and 
 determining the first person is within the predefined zone associated with the rack comprises determining that:
 the first pixel column of the pixel location for the first person is within the range of pixel columns in the frame; and 
 the first pixel row of the pixel location for the first person is within the range of pixel rows in the frame. 
 
 
     
     
       3. The system of  claim 1 , wherein the one or more processors are further configured to:
 determine a probability for each of the first plurality of items in the first digital cart; and 
 determine the first identified item is associated with a highest probability from among the determined probabilities for the first plurality of items in the first digital cart before removing the first identified item from the first digital cart associated with the first person. 
 
     
     
       4. The system of  claim 3 , wherein the probability for each of the first plurality of items in the first digital cart is inversely proportional to a distance between the first person and the rack. 
     
     
       5. An object tracking method, comprising:
 receiving from a sensor a frame of at least a portion of a rack within a global plane for a space, wherein:
 the global plane represents (x,y) coordinates for the space; 
 the frame comprises a plurality of pixels; 
 each pixel from the plurality of pixels is associated with a pixel location comprising a pixel row and a pixel column; 
 the plurality of pixels of the frame depict at least a first person and a second person; and 
 the frame comprises a predefined zone associated with the rack, wherein the predefined zone is proximate to a front of the rack; 
 
 storing a first digital cart associated with the first person, wherein the first digital cart identifies a first plurality of items; 
 storing a second digital cart associated with the second person, wherein the second digital cart identifies a second plurality of items; 
 receiving the frame; 
 determining a pixel location for the first person, wherein the pixel location for the first person comprises a first pixel row and a first pixel column of the frame; 
 determining a pixel location for the second person, wherein the pixel location for the second person comprises a second pixel row and a second pixel column of the frame; 
 determining a first person is within the predefined zone associated with the rack in the frame based on the pixel location for the person; 
 determining the second person is not within the predefined zone associated with the rack in the frame based on the pixel location for the second person; 
 leaving unmodified the second digital cart of the second person; 
 identifying a plurality of items in a digital cart associated with the first person; 
 identifying a first item from the plurality of items associated with the first person; and 
 removing the first identified item from the digital cart associated with the first person. 
 
     
     
       6. The method of  claim 5 , wherein determining the first person is within the predefined zone associated with the rack comprises determining that:
 the first pixel column of the pixel location for the first person is within a range of pixel columns in the frame; and 
 the first pixel row of the pixel location for the first person is within a range of pixel rows in the frame. 
 
     
     
       7. The method of  claim 5 , further comprising:
 determining a probability for each of the first plurality of items in the first digital cart; and 
 determining the first identified item is associated with a highest probability from among the determined probabilities for the first plurality of items in the first digital cart before removing the first identified item from the first digital cart associated with the first person. 
 
     
     
       8. The method of  claim 7 , wherein the probability for each of the first plurality of items in the first digital cart is inversely proportional to a distance between the first person and the rack. 
     
     
       9. A non-transitory computer readable medium storing instructions that when executed by a processor cause the processor to:
 receive from a sensor a frame of at least a portion of a rack within a global plane for a space, wherein:
 the global plane represents (x,y) coordinates for the space; 
 the frame comprises a plurality of pixels; 
 each pixel from the plurality of pixels is associated with a pixel location comprising a pixel row and a pixel column; 
 the plurality of pixels of the frame depict at least a first person and a second person; and 
 the frame comprises a predefined zone associated with the rack, wherein the predefined zone is proximate to a front of the rack; 
 
 access a first digital cart associated with the first person, wherein the first digital cart identifies a first plurality of items; 
 access a second digital cart associated with the second person, wherein the second digital cart identifies a second plurality of items; 
 receive the frame; 
 determine a pixel location for the first person, wherein the pixel location for the first person comprises a first pixel row and a first pixel column of the frame; 
 determine a pixel location for the second person, wherein the pixel location for the second person comprises a second pixel row and a second pixel column of the frame; 
 determine a first person is within the predefined zone associated with the rack in the frame based on the pixel location for the person; 
 determine the second person is not within the predefined zone associated with the rack in the frame based on the pixel location for the second person; 
 leave unmodified the second digital cart of the second person; 
 identify a plurality of items in a digital cart associated with the first person; 
 identify a first item from the plurality of items associated with the first person; and 
 remove the first identified item from the digital cart associated with the first person. 
 
     
     
       10. The non-transitory computer-readable medium of  claim 9 , wherein determining the first person is within the predefined zone associated with the rack comprises determining that:
 the first pixel column of the pixel location for the first person is within a range of pixel columns in the frame; and 
 the first pixel row of the pixel location for the first person is within a range of pixel rows in the frame. 
 
     
     
       11. The non-transitory computer-readable medium of  claim 9 , wherein the instructions further cause the processor to:
 determine a probability for each of the first plurality of items in the first digital cart; and 
 determine the first identified item is associated with a highest probability from among the determined probabilities for the first plurality of items in the first digital cart before removing the first identified item from the first digital cart associated with the first person. 
 
     
     
       12. The non-transitory computer-readable medium of  claim 11 , wherein the probability for each of the first plurality of items in the first digital cart is inversely proportional to a distance between the first person and the rack.